Choke valve operating attachment for carburetors



March 26, 1935.

J. C. HARBISON CHOKE VALVE OPERATING ATTACHMENT FOR CARBURETORS FiledSept. 16, 1952 JICCIflzrbison Patented Mar. 26, 1935 CHOKE OPERATINGATTACHMENT FOR CARBURETORS Joseph C. Harbison, Eldorado, Ill.Application September 16, 1932 Serial No. 633,525-

10 Claims.

This invention relates to a choke valve operating attachment forcarburetors, and has for its object to provide, in a manner ashereinafter set forth, an automatically operable attachment of the classreferred to for materially reducing the consumption of gasoline, thelatter being one of the constituents of the combustible mixture; forenabling the use of a cheaper grade of gasoline O with satisfactoryresults; for materially reducing the fouling of spark plugs and theflooding of the cylinder of the motor; for attaining easier starting ofthe motor; for obtaining the desired choking action at all times; forreducing the dilution 15 of the lubricant in the crank case thusincreasing the life' of the motor; and to attain these ends in a strong,durable, compact, thoroughly eflicient, conveniently adjustable, readilyinstalled and comparatively inexpensive structure not affected byclimatic conditions and capable of being employed in connection with anyof the forms of carburetors on standard types of automotive vehicles.

To the above ends essentially and to others which may hereinafterappear, the invention,

consists of such parts, and such combination of parts which fall withinthe scope of the invention as claimed.

In the drawing:

Figure 1 is a side elevation of an internalcom-- bustion motor showingthe adaptation therewith of the choke valve operating attachment, thelatter being broken away and partly in longi- Y tudinal section.

Figure 2 is a fragmentary view in top plan illustrating the rocker arm.

Figure 3 is a cross sectional view of the exhaust manifold of the motor.

Referring to the drawing, 1 generally indicates 40 a motor of theinternal combustion type. The

intake and exhaust: manifolds of the motofare designated 2, 3respectively. A thermostat 4 is to be disposed lengthwise of the top ofthe manifold 3, and in the example shown, the latter is peripherallygrooved lengthwise thereof in its upper portion, as at 5, formed at oneend with an extension 6 and at its other end with a lateral lug 7.Arranged within groove 5 is the thermostat 4 secured at one end, as at 8to the extension 6. Carried by lug 7 is a pivot pin 9 for a purpose tobe presently referred to. A cover 10 is provided for thermostat 4. v

The carburetor of the motor is indicated at 11 which opens into acentral, tubular, depending branch 12 of the intake manifold 2. Openinginto branch 12 is a structure for dampening the effect of thefluctuations produced in the branch 12 as they are transferred throughsaid structure to a vacuum cylinder to be hereinafter referred to. Thesaid structure includes an angle-shaped 5 member 14 having a horizontalleg 13 opening into branch 12. The member 14 also includes a verticalpart 15. The inner diameter of part 13 corresponds to the inner diametero1 the lower portion 16 of part 15. The remaining portion 17 10 of thelatter is of greater inner diameter than that of portion 16 therebyproviding part with an internal shoulder 18 constituting a valve seat.The member 14 provides a vacuum dampening chamber 19. Arranged in theportion 17 of member 14 is a vacuum check valve 20 and a .stop 21 forthe latter. The portion 16 of member 14 is formed with an angle-shapedby-pass for establishing communicationbetween chamber 19 from below to'above valve seat 18, A closure cap 23 is secured to the upper end ofpart 15 and is formed with an opening to the wall of which one end of asuction or vacuum pipe 24 is attached. Carried by the portion 16 is aregulating screw 25 for by-pass 22. The part 13- has arranged'therein atits free end a reducing bushing 26. The branch 12 is adapted to havearranged therein' a throttle valve 12. The air intake pipe forcarburetor 11 is indicated at 27 and the latter is to have arrangedtherein a choke Valve 2'7. The stem of the choke valve is indicated at28 and which has attached thereto, exteriorly of pipe 27, a lever 29 foradjusting the position of the choke valve. Swivelly attached to lever 29is a barrel 30 and slidably extending through the latter is a shift rod31 for lever 29. The rod 31 carries and has threadedly engagingtherewith a pair of spaced, oppositely shiftable, adjustable abutments32, 33 arranged to selectively contact with the ends of barrel 30 forthe purpose of shifting lever 29.

Supported from a stationary bracket plate 34 is a vacuum cylinder 35having operating therein a piston 36 carried by a piston rod 37 extendedthrough the rear head 38 of cylinder 35. Connected at its rear end inthe forward head 39 of cylinder 35, opening into the latter and havingits outer end attached to and opening into the other end of pipe 24 is aheader 40. Within the cylinder 35 and abutting the inner face of head 39is a sealing gasket or packing member 41 having an opening 42registering with the inner end of .header 40, the latter being ofgreater inner diameter than that of pipe 24. The gasket or 5 member 41is in the form of a disc and has edge engagement with the inner face ofthe cylinder The gasket or member 41 is arranged in the path of piston36, is engaged by the latter and when engaged abuts throughout theforward face of said piston. The latter and header coact to provide avacuum or suction line leading from cylinder 35 to chamber 19.

Suitably attached to the outer or rear end of rod 37 is the forward endof a connecting link. 43, the latter having its rear end suitablyconnected to the lower end of the lever 29. Attached to the lower end oflever 29 is the forward end of a coiled controlling spring 44, thelatter having its rear end anchored to a stationary angleshapedsupporting bracket 45. Pivotally supported upon the bracket 45 is ahorizontally disposed rocker arm 46 to which is attached the rear end ofshift rod 31.

The attachment includes an upstanding lever 4'7 controlled from thethermostat 4. The lever 47 is connected atits upper end, as at 48 to thethermostat 4, and is mounted on pivot arm 9 in proximity to said upperend. The lower end of lever 47 is attached to the forward end of a pullrod 49, the latter having its rear end connected to rocker arm 46. l

The rear head 38 of cylinder 35 is provided with a pair of spaced ports50, 51 which can open directly into the atmosphere, or port 50 may openinto a check valve 52 attached to head 38 and port 51 opens into. aregulating" valve 53. The use of check valve 52 and regulating valve 53-is only necessary on highly sensitive motors.

When the motor is cold the lever 47 is held in the position shown by thecontracting of thermostat 4 which also controls the movement of rockerarm 46 and shift rod 31 through pull rod 49.- The contraction of spring44 draws to the position shown the link 43, rod 3'7, piston 36 and lever29.- The movement of these elements rearwardly will be arrested byabutment 32 and in such rearward movement will cause the air to pass outfrom cylinder 35 through ports 50, 51.

Now when the motor is started, a vacuum is formed in the intake manifoldand chamber 19, but is stopped by check valve 20, it must pass throughby-pass 22 where its speed oftravel can be regulated by the screw 25.The air passing through by-pass 22 will cause a vacuum to be formed inthe vacuum or suction line and cylinder 35 which causes the piston tomove forwardly thereby the. connections between the piston and lever 29will provide for the opening of the choke valve, but when the barrel 30comes in contact with adjustment 33 the opening movement of the Y chokevalve is checked and further movement thereof is controlled by thethermostat and the connections between the latter and lever 29.

Should the movement'and opening of the choke valve be too fast for asuitable mixture, the motor will sneeze or spit then the vacuum will beinstantly changed to pressure in the cylinder thereby allowing thespring to act to instantly close the choke valve. a

The quick choking of the motor when it sneezes or spits is obtained bythe use and action of check valves 20', 52. Also the choker gives aslightly richer mixture when the motor is suddenly and violentlyaccelerated before normal operating temperature is reached. This iscaused by a slight drop in the vacuum due to the quick open- As themotor warms up to normal operating temperature abutment 33 continues tomovein a right hand direction with shift rod 31, caused by the expansionof thermostat until full operating temperature is reached when pistonwill test against gasket 41 thus sealing the vacuum and abutment 32 willbe in contact with swivel barrel thus preventing the spring from closingthe choker, until the motor has been stopped long enough for a decreaseof temperature, when the thermostat will gradually contract inproportion to the temperature of the motor thus giving at all times amixture suited to the temperature requirements of the motor by theproper control of the choker valve.

The purpose of the vacuum dampening cham her is to eliminate pulsationsof piston when the motor pistons pass dead center.

By the use of reducing bushing, vacuum check valve and by-pass a higherratio of vacuum is maintained in the vacuum dampening chamber than inthe vacuum pipe and vacuum cylinder thus preventing chattering andvibrating of piston. Also that the gasket bearing area of cylinder head39 not to be confined to any certain-relation to other parts but is tobe of such area as to cause the vacuum to hold piston snug against thegasket as soon as its movement is uninterrupted by the abutment 33.

What I claim is:-- r

1. In an automatically operable choke valve operating attachment forcarburetors of internal' combustion engines, the combination with theintake'manifold', choke valve and the block of the engine, of a vacuumcylinder adjacent said manifold having a head formed with a single portand a head formed with a. pair of ports and a reciprocatory pistonelement operating therein and through said double ported head, a vacuumline opening at one end thereof into said cylinder and attached to saidsingle ported head, a valve controlled structure opening into the otherend of said line and into the intake manifold of the engine and providedwith means substantially as described having provisions for dampeningthe effect of the fluctuations produced in the intake manifold as theyare transmitted to said cylinder, a normally stationary choke valveopening and closing lever, a controlling spring attached at one endthereof to one end of said lever and having its other end anchored withthe engine block, an operating connection for said lever secured to thesaid end of the latter and to and operated from saidpiston element, athermostatically operated lever, and a shiftable mechanism slidablyconnected to the choke valve operating lever and to and operated fromthe thermostatically operated lever for limiting the range of the chokevalve operation.

2. In an automatically operable choke valve operating attachment forcarburetors of internal combustion engines, the combination with theintake manifold, choke valve and the block of the engine, of a vacuumcylinder adjacent said manifold having a head formed with a single portand a head formed with a pair of ports and a piston element operatingtherein and through said double ported head, a vacuum line opening atone end thereof into said cylinder and attached to said single portedhead, a valve controlled structure providing for dampening the effect ofthe fluctuations produced in the intake manifold as they are transmittedto the vacuum cylinder and including a valve chamber opening at one endinto the other end of said line and at its other end into the intakemanifold, a

valve within said chamber, a seat for the valve, a by-pass'extendingfrom below 'to above said seat and a controlling means for the by-pass,a normally stationary choke valve operatinglever, a controlling springattached at one end thereof to one end of said lever and having itsother end anchored with the engine block, an operating connection forsaid lever secured to the said end of the latter and to and operatedfrom said piston element, a thermostatically operated lever, and ashiftable mechanism slidably connected to the choke valve operatinglever and to and operated from said thermostatically operated 1ever forlimiting the range of the choke valve operation.

3. An automatically operable choke valve operating attachment of theconstruction as set forth in claim 1 whereby the said shiftablemechanism includes spaced parallel adjustable parts for controlling theextent of the sliding movement thereof in opposite directions withrespect to the choke valve operating-lever.

4. An automatically operable choke valve operating attachment of theconstruction as set .forth in claim 2 whereby the said shiftaiblemechanism includes spaced parallel adjustable parts for controlling theextent of the sliding movement thereof in opposite directions withrespect to the choke valve operating lever.

5. An automatically operable choke valve operating attachment of theconstruction as set forth in claim '1 having combined therewith a gasketarranged within the vacuum cylinder in juxtaposition with respect to theinner face of the single ported head of the cylinder and engageable bythe piston element to provide a vacuum seal. y

6. An automatically operable choke valve operating connection of theconstruction as -set forth in claim 2 having combined therewith a gasketarranged within the vacuum cylinder in juxtaposition with respect to theinner face of the single ported head of the cylinder and engageable bythe piston element to provide a, vacuum seal. r

7. In an automatically operable choke valve I operating attachment forcarburetors of internal combustion engines, the combination with theintake manifold, choke valve and the block of the engine, of a vacuumcylinder adjacent said manifold having a head formed with a single portand a head formed with a pair of ports and a reciprocatory pistonelement operating therein and through said double ported head, a vacuumline opening at one end thereof into said cylinder and attached to saidsingle ported head, a valve controlled structure opening into the otherend of said line and into the intake manifold of the engine and providedwith means sub-' stantially as described-having provisions for dampeningthe effect of the fluctuations produced in the intake manifold as theyare transmitted to said cylinder, a normally stationary choke valveopening and closing lever, a controlling spring attached at-one endthereof to one end of said lever and having its other end anchored withthe engine block, an operating connection for said lever 'secured to thesaid end of the latter and to and operated from said piston element, athermostatically operated lever, and a shiftable mechanism slidablyconnected to the choke valve operating lever and to and operated fromthe thermostatically operated lever for limitingthe range of the chokevalve operation, said mechanism including operating attachment forcarburetors of internal combustion engines, the combination with theintake manifold, choke valve and the block of the engine, of a vacuumcylinder adjacent said manifold having a single ported and a double,

ported head and a piston element operating therein and through saiddouble ported head, a vacuum line opening at one end thereof into saidcylinder and attached to said single ported head, a valve controlledstructure providing for dampening the effect of the fluctuationsproduced in the intake manifold as they are transmitted to the vacuumcylinder and including a valve chamber opening at one end into the otherend of said line and at its other end into the intake manifold, a valvewithin said chamber, a

seat for the valve, a by-pass extending frombelow to above said seat anda controlling means for the by-pass a normally stationary choke valveoperating lever, a contrblling spring attached at one end thereof to oneend of said lever and having its other end anchored with the engineblock, an operating connection for" said lever secured to the said endof the latter and to and operated from said piston element,

a thermostatically operated lever, and a shiftl5 able mechanism slidablyconnected to the choke valve operating lever and to and operated fromsaid thermostatically operated lever for limiting the range of the chokevalve operation, said mechanism including spaces paralleladjustableparts for controlling the extent of the sliding movement thereof inopposite directions with respect to the choke valve operating lever, anda gasket arranged in said cylinder in juxtaposition with respect to theinner face of said single ported head and engageable by the pistonelement to provide a vacuum seal.

9. In an automatically operable choke valve operating attachment forcarburetors of internal combustion' engines, the combination with theintake manifold, choke valve and the block of the engine, of a vacuumcylinder adjacent said manifold having a head formed with a single portand a head formed with a pair of ports and a reciprocatory pistonelement operating therein and through said double ported head, a vacuumline opening at one end thereof into-said cylinder and attached to saidsingle-ported head, a valve controlled structure opening into the otherend of said line and into the intake manifold of the engine and providedwith means substantially as described having provisions for dampeningthe effect of the fluctuations produced in the intake manifold as theyare transmitted to said cylinder, a normally stationary choke valveopening and closing lever, a controlling spring attached at one endthereof to one end of said lever andhaving its other end anchored withthe engine block, an operating connection for said lever secured to thesaid end of the latter and to and operated-from said piston element, athermostatically operated lever, and a shiftable mechanism slidablyconnected to the choke valve operating lever and to and operated fromthe thermostatically operated lever for limiting the range of the chokevalve operation, said mechanism including a pivoted rocker arm, a. shiftrod pivotally connected at its ends respectively to said arm and to saidthermostatically operated lever and a pull bar pivotally connected tosaid arm and slidably connected to said choke valve operating lever.

10. In an automatically operable choke valve operating attachment forcarburetors of internal combustion engines, the combination with theintake manifold; choke valve and the block of the engine, of a vacuumcylinder adjacent said manifold having a head formed with a single portand a head'formed with a pair of ports and a reciprocatory pistonelement operating therein and through said double ported head, a vacuumline opening at one end thereof into said cylinder and attached to saidsingle ported head, a valve controlled structure opening into theotherend of said line and into the intake manifold of the engine andprovided with means substantially as described having provision fordampening the effect of the fluctuations produced in the intake manifoldas they are transmitted to said cylinder, a normally stationary chokevalve opening and closing lever, a controlling spring attached at oneend thereof to one end of said lever and having its other end anchoredwith the engine block, an operating connection for said lever secured tothe said end of the latter and to and operated from said piston element,a thermostatically operated lever, and a shiftable mechanism slidablyconnected to the choke valve operating lever and to and operated fromthe thermostatically operated 1ever for limiting the range of the chokevalve operation, said mechanism including a pivoted rocker arm, a shiftrod pivotally. connected at its ends respectively to said arm and tosaid ried by said choke valve operating lever for slidably and swivellyconnecting to such valve said 20 pull bar.

JOSEPH C. HARBISON.

